Hearings instruments may be inserted either partially or completely into a user's ear canal. Typically, hearing instruments, especially custom hearing instruments, must be constructed to minimize feedback when deployed in the user's ear canal.
Existing construction methods and structures for custom hearing instruments do not allow consistent feedback performance and typically require many iterations during manufacture to position an electronic assembly inside a housing of the hearing instrument before a satisfactory performance is achieved, e.g. with respect to feedback.
Often, a closing procedure is done by a trial and error method with an assembly worker moving the electronic assembly within the housing chamber to try to achieve feedback-free operation. Such a procedure may take a significant amount of time. Further, there is no guarantee that the performance will be satisfactory, e.g. possible spikes on a frequency response may still exist because of internal feedback.